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  <div class="section" id="module-builtins">
<span id="builtins-built-in-objects"></span><h1><a class="reference internal" href="#module-builtins" title="builtins: The module that provides the built-in namespace."><code class="xref py py-mod docutils literal notranslate"><span class="pre">builtins</span></code></a> — Built-in objects<a class="headerlink" href="#module-builtins" title="Permalink to this headline">¶</a></h1>
<hr class="docutils" />
<p>This module provides direct access to all ‘built-in’ identifiers of Python; for
example, <code class="docutils literal notranslate"><span class="pre">builtins.open</span></code> is the full name for the built-in function
<a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a>.  See <a class="reference internal" href="functions.html#built-in-funcs"><span class="std std-ref">Built-in Functions</span></a> and <a class="reference internal" href="constants.html#built-in-consts"><span class="std std-ref">Built-in Constants</span></a> for
documentation.</p>
<p>This module is not normally accessed explicitly by most applications, but can be
useful in modules that provide objects with the same name as a built-in value,
but in which the built-in of that name is also needed.  For example, in a module
that wants to implement an <a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a> function that wraps the built-in
<a class="reference internal" href="functions.html#open" title="open"><code class="xref py py-func docutils literal notranslate"><span class="pre">open()</span></code></a>, this module can be used directly:</p>
<div class="highlight-python3 notranslate"><div class="highlight"><pre><span></span><span class="kn">import</span> <span class="nn">builtins</span>

<span class="k">def</span> <span class="nf">open</span><span class="p">(</span><span class="n">path</span><span class="p">):</span>
    <span class="n">f</span> <span class="o">=</span> <span class="n">builtins</span><span class="o">.</span><span class="n">open</span><span class="p">(</span><span class="n">path</span><span class="p">,</span> <span class="s1">&#39;r&#39;</span><span class="p">)</span>
    <span class="k">return</span> <span class="n">UpperCaser</span><span class="p">(</span><span class="n">f</span><span class="p">)</span>

<span class="k">class</span> <span class="nc">UpperCaser</span><span class="p">:</span>
    <span class="sd">&#39;&#39;&#39;Wrapper around a file that converts output to upper-case.&#39;&#39;&#39;</span>

    <span class="k">def</span> <span class="fm">__init__</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">f</span><span class="p">):</span>
        <span class="bp">self</span><span class="o">.</span><span class="n">_f</span> <span class="o">=</span> <span class="n">f</span>

    <span class="k">def</span> <span class="nf">read</span><span class="p">(</span><span class="bp">self</span><span class="p">,</span> <span class="n">count</span><span class="o">=-</span><span class="mi">1</span><span class="p">):</span>
        <span class="k">return</span> <span class="bp">self</span><span class="o">.</span><span class="n">_f</span><span class="o">.</span><span class="n">read</span><span class="p">(</span><span class="n">count</span><span class="p">)</span><span class="o">.</span><span class="n">upper</span><span class="p">()</span>

    <span class="c1"># ...</span>
</pre></div>
</div>
<p>As an implementation detail, most modules have the name <code class="docutils literal notranslate"><span class="pre">__builtins__</span></code> made
available as part of their globals.  The value of <code class="docutils literal notranslate"><span class="pre">__builtins__</span></code> is normally
either this module or the value of this module’s <a class="reference internal" href="stdtypes.html#object.__dict__" title="object.__dict__"><code class="xref py py-attr docutils literal notranslate"><span class="pre">__dict__</span></code></a> attribute.
Since this is an implementation detail, it may not be used by alternate
implementations of Python.</p>
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